[clang-cl] Implement support for /std

/std: supports two arguments, c++14 and c++latest.  Currently, c++latest
maps to c++1z but this might change down the road.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@273841 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Driver/CLCompatOptions.td b/include/clang/Driver/CLCompatOptions.td
index 5e85b618884205ecbd3ba745c1c496d0b8289e29..98d3f992f6e417af98a51978e44649f1ea4add4c 100644 (file)
--- a/include/clang/Driver/CLCompatOptions.td
+++ b/include/clang/Driver/CLCompatOptions.td
@@ -120,6 +120,8 @@ def _SLASH_Qvec_ : CLFlag<"Qvec-">,
 def _SLASH_showIncludes : CLFlag<"showIncludes">,
   HelpText<"Print info about included files to stderr">,
   Alias<show_includes>;
+def _SLASH_std : CLCompileJoined<"std:">,
+  HelpText<"Language standard to compile for">;
 def _SLASH_U : CLJoinedOrSeparate<"U">, HelpText<"Undefine macro">,
   MetaVarName<"<macro>">, Alias<U>;
 def _SLASH_W0 : CLFlag<"W0">, HelpText<"Disable all warnings">, Alias<w>;

diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index c4ac773edeea9a90fa39b1e3693de17fd7bcf3ee..0a3cc02fd8b53ce0d1263cf0c89e2cfe2272d53c 100644 (file)
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -5362,10 +5362,25 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   bool IsMSVC2015Compatible = MSVT.getMajor() >= 19;
   if (ImplyVCPPCXXVer) {
-    if (IsMSVC2015Compatible)
-      CmdArgs.push_back("-std=c++14");
-    else
-      CmdArgs.push_back("-std=c++11");
+    StringRef LanguageStandard;
+    if (const Arg *StdArg = Args.getLastArg(options::OPT__SLASH_std)) {
+      LanguageStandard = llvm::StringSwitch<StringRef>(StdArg->getValue())
+                             .Case("c++14", "-std=c++14")
+                             .Case("c++latest", "-std=c++1z")
+                             .Default("");
+      if (LanguageStandard.empty())
+        D.Diag(clang::diag::warn_drv_unused_argument)
+            << StdArg->getAsString(Args);
+    }
+
+    if (LanguageStandard.empty()) {
+      if (IsMSVC2015Compatible)
+        LanguageStandard = "-std=c++14";
+      else
+        LanguageStandard = "-std=c++11";
+    }
+
+    CmdArgs.push_back(LanguageStandard.data());
   }
 
   // -fno-borland-extensions is default.

diff --git a/test/Driver/cl-options.c b/test/Driver/cl-options.c
index ce63aba9d42d384c4d5368953161988a7a7c14f2..cd8d0c0cc559dbac4860ff6f908feb4d921fe3ee 100644 (file)
--- a/test/Driver/cl-options.c
+++ b/test/Driver/cl-options.c
@@ -452,6 +452,12 @@
 // RUN: %clang_cl -fmsc-version=1900 -TP -### -- %s 2>&1 | FileCheck -check-prefix=CXX14 %s
 // CXX14: -std=c++14
 
+// RUN: %clang_cl -fmsc-version=1900 -TP -std:c++14 -### -- %s 2>&1 | FileCheck -check-prefix=STDCXX14 %s
+// STDCXX14: -std=c++14
+
+// RUN: %clang_cl -fmsc-version=1900 -TP -std:c++latest -### -- %s 2>&1 | FileCheck -check-prefix=STDCXXLATEST %s
+// STDCXXLATEST: -std=c++1z
+
 // RUN: env CL="/Gy" %clang_cl -### -- %s 2>&1 | FileCheck -check-prefix=ENV-CL %s
 // ENV-CL: "-ffunction-sections"